Specific Process Knowledge/Characterization/SIMS: Secondary Ion Mass Spectrometry: Difference between revisions

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=== Typical application of SIMS ===
SIMS is the most sensitive technique for elemental composition. It is therefore ideal if you want to check doping profiles or for contaminations.
A typical application would be to check the concentration profile of boron doping in silicon. In that case one would put two samples into the SIMS.
* A reference sample with a known boron profile
* A sample

Revision as of 12:37, 31 August 2015

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Atomika SIMS

Atomika SIMS: positioned in the basement of building 346 (underneath the cleanroom).


The Atomika SIMS analyses the composition of a sample by secondary ion mass spectroscopy. By using either oxygen or cesium ions accelerated by a high tension the surface of the sample is sputtered off as ions. These ions are analysed in a mass spectrometer and one can determine the elemental composition as a function of depth. If compared to signals from reference materials one can quantify the atomic composition - in certain cases down to extremely low concentrations (ppm). Doping levels and impurities may be determined.

Please note that no user will be instructed on the SIMS. Danchip staff will run your samples.

The user manual and technical information and contact information can be found in LabManager:

The Atomika SIMS in Labmanager

An overview of the performance of the SIMS

Purpose Determination of atomic composition
  • Doping level
  • Sample contamination
Performance Measurement accuracy depends on
  • Which atoms to be analysed
  • The sample morphology (flat samples are much more suited than particles)
Process parameters Ion gun parameters
  • Acceleration voltages and focusing lens parameters
  • Gas inlet pressures and apertures
Mass spectrometer parameters
  • Detector biases and range
  • Scan parameters such as raster size, speeds and pattern
Sample position
  • Angle towards spectrometer
  • For non-conducting samples: Flood gun parameters
Sample requirements Substrate material allowed
  • In principle all materials
Substrate size
  • The samples must be cut into 5x5 or 7x7 mm pieces
  • Other types of samples must be mounted onto appropriately sized carriers
Batch size
  • The sample holder carries up to 6 samples at the time